Is it possible to set an HttpOnly Cookie from one domain to another subdomain

Solution 1:

This is possible. In fact I just did it.

On your frontend, using Axios:

    const baseURL = "https://api.example.com";

    const api = axios.create({
      baseURL,
      withCredentials: true,
    });

On your backend, using Express:

app.use(
  cors({
    origin: "https://www.example.com",
    credentials: true,
  })
);

app.post("/login", async (req, res) => {
      res.cookie("someCookie", someCookieValue, {
      secure: true,
      domain: "example.com",
      httpOnly: true,
    });
})